Roy L. Moodie 445 
specimen at an angle of about forty-five degrees with a reflector on the 
opposite side so as to illuminate the object uniformly gives the best 
results. ‘The specimens are placed in a broad, shallow glass dish with just 
enough clear glycerin to cover them. The dish should be raised somewhat 
on small blocks so as to throw the background out of focus. Two of the 
half-tones in the present essay were prepared in this way. 
For the purpose of determining the presence or absence of epiphyses 
in the Reptilia the following groups have heen investigated and will be 
discussed in the order named: Chelonia, Plesiosauria, Crocodilia, Lacer- 
tilia and Sphenodon. 
Fic. 1. Limbs and girdles of a young Chelydra 44 mm. in length; no 
epiphyses. 114 natural size. 
The turtles studied consist of embryos of Chelydra, Graptemys, Chryse- 
mys, Trionya and Aromochelys, the young of Chelydra serpentina Linné 
and Chrysemys picta Hermann, together with adult skeletons of many 
genera, notably Chelydra, Chrysemys, Testudo, Chelys, Chelone, Cistudo 
and T'rionyx. 
Very little is to be learned in regard to epiphyses from the embryos of 
the turtles. In the lizards where epiphyses are found they are not formed 
until after the time of hatching from the egg. They are seen as minute 
points in the cartilage at the ends of the limb bones of a young lizard, 
Sceloporus, two days old. The turtle specimens which were investigated 
particularly for the presence of epiphyses, range from very small embryos 
in which the carapace is not yet formed to and including the stages of 
